Our structural engineers will provide direction related to where the appropriate attachment point should be made. The vast majority of the time it will be on the top chord of the member if it's a single point connection. If it's a trapeze connection then attachment to the bottom chord is usually acceptable. For single point connections on lighter weight members the attachment to a bottom flange can cause a twisting motion of the member.
When you have heavy steel members such as "W" shapes it most of the time won't matter. But if there is any doubt or to keep from redoing your work, ask the S.E. ahead of time if there are any hanging and support restrictions. Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [email protected] http://www.ch2m.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Hinson, Ryan Sent: Thursday, January 28, 2010 5:54 PM To: '[email protected]' Subject: Hanging. bracing, or restraining from the bottom chord of a truss or joist I have always been instructed to hang, trapeze, or brace to the top chord of trusses, joists, and other structural members. I believe it is good practice to do so since the top chord is restrained via the attached roof from lateral movement whereas the bottom chord is not except where cross bracing is attached. That being said, is there any specific code reference that mandates this; or is it strictly up to the structural engineer to determine whether the bottom chord can handle the possible generated loads? Ryan L. Hinson, EIT, NICET III Fire Protection Systems Designer, Aviation and Facilities Group Minneapolis-St. Paul Office Burns & McDonnell 8201 Norman Center Drive, Suite 300 Bloomington, MN 55437 Direct: 952-656-6003 Ext 3662 Fax: 952-229-2923 www.burnsmcd.com<BLOCKED::www.burnsmcd.com> Proud to be one of FORTUNE's 100 Best Companies To Work For _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
